P0220

P0220 sets when the ECM sees the throttle position sensor B circuit out of its expected operating window on a drive-by-wire (ETC) vehicle; TPS-B is the second potentiometer track inside the electronic throttle body that runs inverse to TPS-A so the PCM can cross-check the two against each other. Cheapest-first diagnosis: with key-on engine-off, backprobe the TPS-A and TPS-B signal wires at the throttle body connector and watch a graphing scan tool or DVOM — TPS-A should read approximately 0.5 V at closed throttle and sweep smoothly to about 4.5 V at WOT, while TPS-B mirrors the opposite direction (roughly 4.5 V closed dropping to 0.5 V WOT) on most Toyota/Honda/GM ETC bodies (some Ford and VW invert this, so reference the FSM). Verify the shared 5 V reference at the connector is steady at 4.9 to 5.1 V and the sensor ground reads under 100 mV to chassis. Caveat: P0220 is essentially nonexistent on pre-ETC cable-throttle vehicles because they only have a single TPS; if you see this code on a 1990s vehicle, suspect a misidentified code or a non-OEM retrofit harness.

Vehicle-specific patterns: 2005-2010 Honda Odyssey/Pilot 3.5L — the integrated TPS inside the ETB fails as a unit; Honda does not sell the sensor separately, throttle body assembly replacement plus idle relearn is required. 2007-2014 Toyota Camry/RAV4 2.5L (2AR-FE) — same integrated-TPS pattern, replace ETB part 22030-0H030 or family equivalent. 2007-2013 GM 5.3L/6.0L truck (LY5/LY6) — carbon buildup on the throttle plate shifts TPS-B learned position; BG 44K induction clean plus throttle relearn fixes it before parts get thrown. 2006-2011 VW/Audi 2.0T (BPY/CCTA) — throttle body J338 internal sensor failure, scan-tool basic-settings adaptation after replacement is mandatory. Estimated repair: $120 to $650.